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The K7RA Solar Update


Tad Cook, K7RA, Seattle, reports: Sunspot numbers and solar flux index were both declining by the end of the October 28 – November 3 reporting week, but averages for both numbers were higher than reported in last week’s bulletin, ARLP044. The average daily sunspot number increased from 54.9 to 67.6, while average daily solar flux jumped from 95.7 to 102.

Coronal Mass Ejection (CME) activity through the week drove geomagnetic numbers much higher. Average daily planetary A index increased from 4.4 to 12, and average daily middle latitude A index went from 3.6 to 9. On November 4 the planetary A index was 69, and Alaska’s College A index was 131. reported that what it called a “cannibal CME” struck Earth at 2000 UTC on Wednesday, November 3, and that this would spark a strong geomagnetic storm, and boy, did it ever! With aurora observed in US below northern-tier states, it had a pronounced negative effect on HF propagation on Thursday, November 4. For a time on Thursday, testing propagation paths using FT8 and PSK Reporter, I could see no propagation above 20 meters.

Here’s more on that CME from, “Sun outburst goes ‘cannibal’ as fast new blob overtakes a slower one

At 0326 UTC on November 5, the Australian Space Forecast Centre noted that, although conditions have quieted down, a southward turn of the interplanetary magnetic field may cause another increase in geomagnetic activity.

I received several reports this week that 10 meters is back”

Jon Jones, N0JK, in Kansas noted on November 4:

“No (VHF) enhancement in Kansas from the CME impact yet. Last weekend in the CQ WW SSB contest, 10 meters was open both days. I logged HD8R Galapagos Islands and other stations using 5 W and a mobile antenna. Best DX: D4F.

“ZF5T was very loud Sunday afternoon around 2015 UTC on 10 meters.”

A NOAA prediction at 2118 UTC on November 4 predicted solar flux at 90 on November 5; 85 on November 6 – 7; 80 on November 8 – 12; 88 on November 13 – 14; 89 on November 15; 92 on November 16 – 19; 93 on November 20; 95 on November 21 – 27; jumping to 103, 102, 100, and 98 on November 28 – December 1; 96 on December 2 – 4; 92 and 90 on December 5 – 6; 88 on December 7 – 11; 89 on December 12, and 92 on December 13 – 16.

Predicted planetary A index is 18, 15, and 8 on November 5 – 7; 5 on November 8 – 14; 10 and 8 on November 15 – 16; 5 on November 17 – 29; 8 on November 30 – December 1; 5 on December 2; 12, 10, and 8 on December 3 – 5; 5 on December 6 – 11, and 8 on December 12 – 13.

Here’s the geomagnetic activity forecast for November 5 – December 1 from F.K. Janda, OK1HH. The geomagnetic field will be:

  • quiet on 18 – 19, 23, 25

  • quiet to unsettled on November 9, 12 – 13, 17, 20, 22, 24 

  • quiet to active on November 5, 10 – 11, 21, 26 – 27 

  • unsettled to active on November 6 – 8, 14, 16, 28 

  • Conditions will be active to disturbed November (15, 29,) 30, December 1 

  • Solar wind will intensify on November (8,) 9 – 10, (11,) 16 – 17, (29 – 30), December (1 – 2,) 3 – 4

Note: Parentheses mean lower probability of activity enhancement.

Southgate Amateur Radio News included this report, “Solar Cycle 25 October report from AA6XE.”

N8II in West Virginia, reported:

“It certainly was a great month just past. DXpeditions have resumed, quite a few to Africa and all of them worked on 12 and 10 meters. C5C, The Gambia is also active, and TL7M, Central African Republic heard on 12, 15, and 20 meters, CW. 7P8RU is a Russian group worked on 30 – 10 meters on CW and 17 and 12 meters on SSB. Hearing Russia and Scandinavia on 15 has been a nearly daily occurrence. 12 meters has been open to Europe daily for about the last 10 days. South America is in daily on 10, with best conditions around 1900 – 2000 UTC; 15 begins opening to Europe at around 1240 UTC.

“At 1645 UTC, most Europe were gone. 12-meter signals vary day to day with quite a few new countries going into the log, such as Kuwait, Israel, Norway, Sweden, Finland, Faeroe Islands, Gibraltar, and Guernsey — many on both SSB and CW. CW countries worked on 12 meters now are 103 versus about 80 before September, 15 meters now 198, and 10 CW now 98.

“A major solar storm was forecast for the CQ World Wide phone contest October 30 – 31. When the K index peaked at 5 at 1500 UTC on the October 31, we were working loud Europeans — even northern Europe. At the start of the contest, I was on 20 and, very strangely, South American and Caribbean signals were way down with decent conditions to East Asia, excluding Japan. I heard about nine Chinese stations in just over the first hour, putting three into the log including B0A at S-9 + 20 dB from rare zone 23.

“I also heard the Philippines, worked RN0CT in Zone 19, 7Q6M Malawi, and D4L Cape Verde in first hour. Saturday morning, 15 was opening around at around 1120 UTC to Europe. There were loud signals from all over EU, and Kazakhstan was heard. At 1329 UTC, I switched to 10 and found a few Europeans; first worked were Hungary, Slovenia, Italy, Ireland, and a very loud E7AA in Bosnia. The opening was spotlight type to relatively small areas most of the Mediterranean, many from Sicily. EW5A in Belarus was the only northern European station logged at 1414 UTC for Zone 16.

“Right around 1430 UTC, Europe faded out. I worked A73A Qatar on a peak, and South America began coming through, with signals poor at first with some good by 1450 UTC. Despite strong signals from Paraguay, Chile, and Argentina, Brazil was not loud enough to work until 1725 UTC; then many showed up through the afternoon until my 2210 UTC sunset. I was lucky to catch ZM4T New Zealand and VK4A right around sunset for Zones 32 and 30. 

“Sunday, I was not expecting much with the rising K index, but 15 sounded pretty normal, and I logged EA1L in Spain at 1228 UTC on 10. It was a struggle to work many stations because of better conditions for stations farther to the northeast in North America. I caught 7P8RU in Lesotho at 1255 UTC. After a short break, 10 meters band blew wide open at 1339 UTC with many calls from Western Europe, including quite a few Dutch and German stations. TK5MH called from Corsica, and 4U1A called from the Vienna International Center. Then gradually northern Europe filled, with OH0V Aland Islands and calls from Lithuania, Sweden, Denmark, Estonia, Norway, and Finland in the 1500 UTC hour. The K index was 5 reported at 1500 UTC, so it seemed strange to be able to work so far north — possibly auroral Es. Most of Europe finally faded by 1656 UTC. Quite an opening, the best of Solar Cycle 25 so far.”

We heard from Mike May, WB8VLC, in Oregon:

“During CQ WW SSB last weekend, 10 meters was sounding like nothing I have heard in 20 years with some Europe in the morning then the typical South America in the afternoon.

“The evening of Saturday, October 30, was the best Asia opening I have heard on 10 with 28.3 to 29 MHz filled with JA stations. The most interesting was the other Asian DX worked aside from Japan: VR2XAN in Hong Kong and DY1T in the Philippines, both in here for around 1 hour at S-9+ along with other big signals from Hawaii, New Zealand, Australia, Guam, the Mariana Islands, and even some weak China on 10 meters.”

Mike sent a long list of stations with S-9 signals on 10 meter SSB, including Cape Verde, Guam, Portugal, Madeira, Galapagos and Brazil. “Even 10 FM was active!” he said.

From Angel Santana, WP3GW, in Puerto Rico:

“Ten meters was the surprise band on this weekend’s contest. I always start on the band and rack up the South Americans, about 26 in an hour which is almost threefold compared to last year. After working some on 15 meters at 1200 UTC for an hour, wow 10 meters was teaming with life like 5 years ago! Worked a few Europeans in half an hour and went and go during the day, including an FR about 1433 UTC. 

“It was not until Sunday morning that 10 got interesting, when I worked early E7AA, who worked only on 10 and was my only Bosnia QSO. Then ZD7, 7P, OH0, 7Q, EA9, pretty easily with low power. At 1930 UTC turned my antenna (manually) toward the US and called on 28.392 MHz, working 56 stations in an hour, 98% of them US stations.

“Can't wait for the ARRL 10-Meter Contest 2021!”

From Simon, GW0NVN:

“Here at Finningley Amateur Radio Society G0GHK, we were shown what the sun can do on Sunday, October 31. Switched to 10 during breakfast to hear a number of strong stations including VK6 having a rag chew and working a few European stations. Coming back to 10 in the afternoon, we had an over 1.5-hour pile-up of W and VE stations.”

Here is an exciting update from Tamitha Skov, WX6SWW.

This weekend is ARRL November Sweepstakes (CW).

Sunspot numbers for October 28 – November 3 were 96, 82, 76, 83, 53, 42, and 41, with a mean of 67.6. The 10.7-centimeter flux was 111.7, 108.4, 107.2, 102.7, 97.7, 97, and 89, with a mean of 102. Estimated planetary A indices were 3, 3, 10, 20, 10, 17, and 21, with a mean of 12. Middle latitude A index was 3, 2, 8, 16, 8, 12, and 14, with a mean of 9.

For more information concerning radio propagation, visit the ARRL Technical Information Service, read “What the Numbers Mean…,” and check this propagation page by Carl Luetzelschwab, K9LA.

A propagation bulletin archive is available. For customizable propagation charts, visit the VOACAP Online for Ham Radio website.

Instructions for starting or ending email distribution of ARRL bulletins are on the ARRL website.

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